There has been provided a hybrid vehicle using as a power source for running (i) an internal combustion engine driven by fuel combustion and (ii) a motor driven by a battery. As disclosed in Patent Documents 1 to 3, for example, a charge-discharge management apparatus is known so as to save fuel consumed by the internal combustion engine of the hybrid vehicle. The charge-discharge management apparatus creates a schedule concerning whether or not to operate the internal combustion engine and the motor and charge the battery along an estimated route. The charge-discharge management apparatus allows a hybrid vehicle control apparatus to provide control in accordance with the schedule.
Road congestion situation or driving situation such as a vehicle speed continuously changes. Thus, it may be difficult to keep the remaining quantity of the battery according to transition of the remaining quantity estimated or predicted based on the schedule while actually running the estimated route. In Patent document 3, in order to address the above difficulty, when transition of SOC (State Of Charge) predicted from the schedule and transition of actual SOC come to be differentiated from each other, the schedule is re-calculated.    Patent Document 1: JP 2000-333305 A (U.S. Pat. No. 6,314,347)    Patent Document 2: JP 2001-183150 A    Patent Document 3: JP 2007-50888 A
From the study of the inventor, the reliability of the schedule is not so perfect (i.e., not 100%) so that re-calculating of the schedule or re-scheduling is not always more useful than not re-calculating. For example, there is a technology to re-calculate the schedule according to the difference between the above predicted SOC and an actual SOC. If such a technology is adopted and repeated, it may result in worsening fuel consumption in comparison with the case where re-calculating the schedule is never made.